Electricity bills have tripled

Can you tell us more about the heat pump, include some photos and say what temperature you have the house set to. The more you include the better.

Hi, thanks for the reply. The bills aren’t estimates as I sent in an up to date reading. I am so ignorant about how this system works but we have 2 rads in the lounge set at 21 degrees on for 8 hours. Bathroom rad on for 2 hours at 21 and upstairs one rad on for two hours. Hot water is set at 60 and we use the shower once or twice a day. Have asked OVO for a visit from the Energy Efficiency Person but there isn’t one in my area.

Without any more to go on this is what I suggest you do: 

Turn the hot water down to 50 degrees C. Make sure you’re only heating it on a schedule, not on ‘reheat’. I heat our hot water at night during my cheap rate hours and again in the afternoon when the outside temperature is warmest. The space heating (ie radiators) won’t get any heat when the hot water cycle is running so do it at a time when you won’t notice it missing. Mine takes about 45 mins. If you have a ‘legionella’ or disinfectant’ cycle enabled you can disable it. It’s reckoned to be unnecessary in a domestic setting where you’re using and refreshing the contents of your hot water cylinder every day.

Next, rather than have the radiators on for a few hours at a time (generally an inefficient way of running a heat pump) run it at a lower temperature for longer hours. Without knowing what heat pump you have it’s a bit difficult to explain the changes you need to make. Mine is a Daikin Altherma 3 and I have a Madoka room sensor. I’ve set the controls to Weather Dependant, which means the radiators are cooler when it’s warm outside and warmer when it’s cool outside. You may have been set up with a fixed flow temperature which is not an efficient way to run it. Open all your radiator valves (the adjustable ones) fully so they all receive heat at the same time. The heat pump needs a good flow of water pumped around and there’s no benefit closing some off here and there. If that sounds extravagant then don’t worry, you’ll save by the hp running at tickover rather than having to burst into life every time a change of heat is called for, as it is currently. You can turn the overall temperature down to use less electricity rather than turn it off. This does all sound involved I know. With more info on your system I might be able to explain better how you can do all this. 

@serennu Have you had an opportunity to alter your heat pump settings ? Has that made a difference ?

Hi @serennu that sounds like a very good idea. Do let us know how you get on. 

Thanks Tim, it really is complicated for an oldie like me. I asked OVO about the Energy Expert visits but my area is not covered at the moment, very disappointed about that as my county Powys are really pushing this Eco4 scheme and I am sure there are others like me in need of help in  understanding the ins and outs of my system. I am waiting now for the organisation to get back to me but was told it would be about 2 weeks because of the bank holiday. They are SevernWye,  a charitable organization and their services are free and they were recommended to me by Warm Wales. Thanks to you and juliamc  for taking the time to help me.

​Thank you for sharing, @serennu. It helps learn what other resources are available if anyone else is in a similar position. 

We will wait to hear how your visit goes!

I don’t know the Vaillant controls unfortunately, however I’m sure the principles are the same for all heat pumps. Does your controller look like this ? 

I should point out that only about half of the electricity usage in the bills total above was due to the heat pump ! Approx 1500 kWh for the three winter months.

It is possible but I would expect to have noticed that separately unless both were connected at the same time. 
It might be possible to check by comparing a sunny day to a cloudy one (should use less power from the grid on a sunny day) or even look at the monitor for the inverter. 

You can but it’s not straight forward unfortunately. It depends on the system, set up etc but generally you would find the CT (probably near the meter) and look for the arrow that’s moulded into the side. It should be on the cable after the meter, pointing back towards the meter .. I’ll try to find a photo. 
If the previous usage noted was before the installation, then a CT positioned incorrectly could add double the solar feed level. (So possibly near to tripling). 
Edit: arrow not always easily visible 

I can’t see a clamp, would it be near my meter or near the heating controls which are situated in my airing cupboard

There doesn’t seem to be anything like that in my meter box